O Potterson CF 20/35, Инструкция по установке и обслуживанию

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Pressure Gauge
A pressure gauge incorporating a fill pressure indicator, covering the range 0-
4 bar (60
lbf/in²) shall be fitted to the system. It should be connected to the sys
tem, preferably atthe same point as the expansion vessel. Its location should
be visible from the filling point.
Expansion Vessel
A diaphragm type vessel to BS. 4814 Part 1 shall be fitted close to the inlet sid
e of the pump. The connecting pipework should not be less than 15 mm
(½ in
nominal).Pipework connecting the expansion vessel should not incorporate va
lves of any sort. Methods of supporting the vessel are supplied by the manufa
cturer. The nitrogen or aircharge pressure of the expansion vessel shall not be
less than the hydrostatic head,
(height of the top point of the system above the expansion vessel). To size the
expansionvessel it is first necessary to calculate the volume of water in the sy
stem in litres. The following volumes may be used as a conservative guide to
calculating the systemvolume.
Boiler Heat Exchanger 6.5 litres
Small Bore Pipework 1 litre per kW of system output
Micro Bore Pipework 7 litres output
Steel Panel Radiators 8 litres per kW of systemoutput
Low Water CapacityRadiators 2 litres per kW of systemoutput
Hot Water Cylinder 2 litres
If the system is extended the expansion vessel volume may have to be increa
sed unless previous provision has been made for the extension. Where a vess
el of thecalculated size is not available, the next available larger size should b
e used.
Page 9
TECHNICAL DATA - Page 10
The boiler flow temperature is controlled at approximately 82˚C. The ve
ssel size can now be determined from the following table where V = system v
olume in litres.
Vessel Charge Pressure (bar) 0.5 1.0